How Do I Decide?

Part 4

The human brain is the most complex object we've discovered in the universe, and every day much of its neural circuitry is taken up with the tens of thousands of decisions we need to make. "How Do I Decide?" is a journey through the unseen world of decisions, and how they get made. We start with a simple one: choosing a flavour of frozen yoghurt, and learn that every decision we make is born of a "winner takes all" competition between rival neural networks. As David ponders the choice before him - mint verses lemon - inside his brain, two rival networks are fighting it out. As one begins to get the upper hand, it causes the other network to be less active, until a threshold is crossed, the decision is made: he goes for mint. Every decision we make is underpinned by this kind of neural conflict, and what’s more, many of these important battles are won, and lost, without us being consciously aware of it. Professor Read Montague reveals that he can be 95% certain about which political party we will vote for based on our brain’s response to disgusting imagery. The more disgusted a brain response is the more likely that person is to vote conservative.